The invention relates to a brake slippage control wherein the deviation of a signal corresponding to the wheel speed from prescribed portion of a reference speed approximated to the vehicle speed is determined and used to change the brake pressure.
In known slippage controls for vehicles, a reference value is recovered from the speeds of one or several vehicle wheels and approximated to the curve of the vehicle speed. One or several percentages of this reference value are formed and compared to the speed signal of the wheel. When the wheel speed signal falls below or exceeds these percentages (e.g. 95% and 80%), which serve as thresholds, control signals are derived and a brake pressure control unit is activated for pressure variation.